[TJHUB]

I currently have an SVS PB13-Ultra and it has brought many good things to my setup. However, recently I went through a very detailed process of speaker placement and room reaction that really showed me the lower end limitations of my beloved B&W 805S's.


What it boils down to is that my 805S's seem to give up around 160Hz and the frequency response (FR) gets out of control. What's really missing is that midbass punch.

The red line is the B&W 805S's running full range. The blue line is with my sub integrated and EQ'd with a Behringer Feedback Destroyer. I used a 160Hz -12db x-over and things sound pretty damn good. Surprisingly good actually.


I've tried every x-over point from 40Hz to 160Hz. I only tried 160Hz because as you can see from the graph, the B&W's have a huge drop off. I figured I'd just see what happens with 160Hz and EQ'd everything.


I now have a good midbass punch and my speakers have never sounded so good. I can honestly say that I really can't locate the sub other than in my mind I know where it is.


Here is a recent photo of my setup:

The speaker are located slightly different now and I have the sub between the left speaker and my entertainment center.


So here is what I'm thinking...


I love my B&W's and I really don't want to change them. I was thinking that I could possibly go to a dual sub setup with one sub located on each side of my entertainment center with my B&W's located on the outside of each. I would like a smaller sub as the PB13U is just a little too big and I'd like the new subs to work well to 160Hz with better sound quality than I have now.


FYI: I'm a music lover first, but HT has to be great as well.


Am I thinking about this wrong? I'm open for suggestions.


My initial thoughts were to pick up dual ULS-15's or maybe a pair of Rythmiks as the HSU's are a bit pricey for me.

 

[Kangaroo128]

As far as the "Punch" you're seeking, I believe that duals will give you a good bit more headroom and allow about 6db of acoustical response over a single.


If you are planning to sell off the PB13, will you contact me and let me know? I've been looking to find one in the used market, and if you could give me a decent price, I'll take it off your hands.

 

[sivadselim]

It's not really your speakers, per se. It is your room. And 160Hz is too high.

 

[Kangaroo128]

I agree, 160hz is much too high. Those speakers should be able to handle 80hz pretty handily.

 

[weverb]

I think your full range graph looks great! It actually looks like you have a couple of peaks at 290 and 690Hz. The rest looks perfect. I would not change a thing. I would spend more time right now listening to your various reference material and give it some time. Maybe try and visit/listen to any near by fellow AVS members set-ups.

 

[T-Bone]

Geez... maybe I need my eyes fixed, but I fail to see the issue with the FR. The black line shows a very flat response low end. And the 805s alone are good to about 38 Hz. Lots of peaks.valleys though.


The dip is not the speaker issue... as sivadselim stated, its a room issue.


-T

 

[craig john]



Quote:
What it boils down to is that my 805S's seem to give up around 160Hz and the frequency response (FR) gets out of control. What's really missing is that midbass punch.

I'm not sure I would interpret your graphs the same way you did. You stated that the speakers "give up" around 160 Hz. It looks to me like the red trace is relatively "flat" from 160 Hz down to about 38 Hz, with variations due to the room. IOW's, these speakers are fully capable of good LF extension, and can be crossed over much lower than 160 Hz.


The blue trace, with the subwoofer crossed in at 160 Hz has a higher average level across the board from 160 Hz down. This tells me that the subwoofer's average level is set higher than the speaker's average level. IOW, the subwoofer is not properly calibrated for level with the speakers. It looks by eye to be set about 6 dB hot. Basically, you've used the subwoofer as a "tone control". The extra punch or kick you feel is due to the higher overall bass level relative to your speakers. If you turned the subwoofer level down so that the overall average level was the same as the speakers, (i.e., calibrated it for level with the speakers), I doubt you would hear or feel the drastic difference you're sensing now. You may *like* the current setup, and that is fine. However, you should make decisions based on the *correct* setup, not the juiced setup.


My suggestion would be to use an 80 Hz crossover and then set the speaker and sub levels for equal average volume, IOW's "calibrate" them. Then redo your graphs. I predict you'll find a flatter overall response. If you *prefer* more bass response than a flat setup gives you, you can add it back in by using the bass tone control, or by increasing the subwoofer level. However, "flat" response should always be your starting point and your point of comparison.


Of course, if you want to add a second sub, there are other benefits besides being able to cross over at 160 Hz. You get lower distortion, higher headroom and flatter FR at more listening positions. These benefits are worth the price of admission, but you still want to calibrate the *combined* output of the 2 subs to be equal to the output of the speakers.


Craig

 

[TJHUB]



Quote:
Originally Posted by sivadselim /forum/post/15409275


It's not really your speakers, per se. It is your room. And 160Hz is too high.

I want to agree with you, and you are most likely correct, but I'm at a loss as to what to do about my room. It's my living room and with some small exception, I can treat it with some panels, but I'm at a loss of just how to proceed.

Quote:
Originally Posted by craig john /forum/post/15409646


I'm not sure I would interpret your graphs the same way you did. You stated that the speakers "give up" around 160 Hz. It looks to me like the red trace is relatively "flat" from 160 Hz down to about 38 Hz, with variations due to the room. IOW's, these speakers are fully capable of good LF extension, and can be crossed over much lower than 160 Hz.


The blue trace, with the subwoofer crossed in at 160 Hz has a higher average level across the board from 160 Hz down. This tells me that the subwoofer's average level is set higher than the speaker's average level. IOW, the subwoofer is not properly calibrated for level with the speakers. It looks by eye to be set about 6 dB hot. Basically, you've used the subwoofer as a "tone control". The extra punch or kick you feel is due to the higher overall bass level relative to your speakers. If you turned the subwoofer level down so that the overall average level was the same as the speakers, (i.e., calibrated it for level with the speakers), I doubt you would hear or feel the drastic difference you're sensing now. You may *like* the current setup, and that is fine. However, you should make decisions based on the *correct* setup, not the juiced setup.


My suggestion would be to use an 80 Hz crossover and then set the speaker and sub levels for equal average volume, IOW's "calibrate" them. Then redo your graphs. I predict you'll find a flatter overall response. If you *prefer* more bass response than a flat setup gives you, you can add it back in by using the bass tone control, or by increasing the subwoofer level. However, "flat" response should always be your starting point and your point of comparison.


Of course, if you want to add a second sub, there are other benefits besides being able to cross over at 160 Hz. You get lower distortion, higher headroom and flatter FR at more listening positions. These benefits are worth the price of admission, but you still want to calibrate the *combined* output of the 2 subs to be equal to the output of the speakers.


Craig

I know you can't confirm this, but this graph is just a measurement I used to see changes. For most music that I listen to, the bass level in actually very balanced if not a little on weak side. I'm far from a bass head and the music I like to listen to most is: Dave Brubeck, Foreplay (VERY bass heavy recordings), Patricia Barber, Diana Krall, Peter White, etc. But I listen to everything from Nine Inch Nails, Tool, Korn, to Yo-Yo Ma.

I worked VERY hard to get my speakers placed for their best measured frequency response and gave things a good listen. I can tell you that my setup has never sounded as good as it does right now. It's funny, but for the most part, only the upper frequencies were affected by speaker placement. The lower end didn't change much at all.


Last week during my speaker placement testing, I forgot to change things back to normal when I powered everything off. I left my main speakers set to large and the sub was powered off. I turned everything on the next day and didn't even realize the sub was off at first. After a track or two played, I noticed a couple of things. I heard a lack of midbass, and more so, I could hear the bass notes getting louder and softer as the music played through the lower frequency range. I thought for one second: "WTF?" I walked over to my sub and noticed it wasn't playing. My next thoughts were: "thank goodness" and "wow, those little B&W's have some decent bass output". If my sub was running so hot, do you think I'd ever have thought is was playing when it wasn't?


Nonetheless, let's just say my sub is balanced and all is well. What I felt was missing from my setup was lack of midbass; like as in NONE. When I play my 805's without the sub, they can really put out a 40Hz tone scary loud, but a kick drum sounds like nothing. Integrating my sub at 80Hz doesn't change this at all. I tried 100Hz and the same. But when I tried 160Hz as an experiment...success.


I realize that 160Hz is incredibly high. I've been doing this stuff for a long time. I'm not saying I understand everything, but I'm a 40 year old guy with enough understanding to be dangerous.


I can't seem to do anything to help those frequency variations below 200Hz. No speaker placement affected those frequencies. I have about 20 graphs and about a hundred measurements figuring all this stuff out. Maybe one issue is how both my speakers and my prepro handle the x-over points:

The top line (red) shows no HP x-over. The subsequent lines below the red line are HP x-over points at: 40, 50, 60, 70, 80, 90, and 100Hz respectively.


Measurements aside, crossing my sub at 80Hz just yields very little midbass and doesn't sound accurate at all. Everything sounds very good right now.


I'd really like a small sub without giving up much or anything in output that the PB13U gives me. My room is rather large at about 6,500cF with a large opening to my dining room. I guess I was hoping to find a pair of subs to help fill in the missing parts on my main speaker's lower end while gaining smaller boxes and possibly better sound quality.


I'm sorry this post is probably just rambling as I have no time to write something intelligent and I'm very tired. I appreciate the comments and I'll try some more testing and measurements with the time off I have coming later this week. I really want to get this figured out...

 

[mayhem13]

Your not rambling, and expecting the B&Ws to put out dynamic midbass is asking alot IMO. What you're actually looking to achieve is more of a blend than a suitable xover point to a mono sub. Adding 'Bass Bins' is not an uncommon practice these days and is gaining more adopters. Two sealed subwoofers employed using the L/R signal and crossed high can be used to blend with the natural rolloff of your mains. You may find plugging the ports a big help( ok everyone...flame away). Then use your existing sub for the LFE channel crossed where you find the subs natural roll off begins. It may be higher up the Freq range than the in room response graphs suggest. Measure 1m from the cone, not the listening position.


This IMO is a clear case of a listener who enjoys something other than a flat FR, and you should follow your ears. Dynamics are a bit hard to get from a single 6.5 midwoofer. My Current DIY mains use 2 6.5 Seas midwoofers in a 2.5 way sealed (the original ported design was too 'dry' for my tastes) with each over a single 12" sealed sub crossed at 100hz. The F3 of my mains are about 75hz so the xover point worked out well for me. Some will say you'll need to high pass the mains but i disagree. If you plug the port, the sealed alignment will move the F3 up higher creating a natural 12db/oct rolloff. The 6.5 midbass will also be relieved of the lower freq, improving the mid range clarity. In essence, your mains will perform more like 801s. You'll have to keep the subs in close proximity to the mains though to alleviate localizations at the higher XO, but like everything in audio...you have to live with the trade offs.

 

[TJHUB]



Quote:
Originally Posted by mayhem13 /forum/post/15411060


Your not rambling, and expecting the B&Ws to put out dynamic midbass is asking alot IMO. What you're actually looking to achieve is more of a blend than a suitable xover point to a mono sub. Adding 'Bass Bins' is not an uncommon practice these days and is gaining more adopters. Two sealed subwoofers employed using the L/R signal and crossed high can be used to blend with the natural rolloff of your mains. You may find plugging the ports a big help( ok everyone...flame away). Then use your existing sub for the LFE channel crossed where you find the subs natural roll off begins. It may be higher up the Freq range than the in room response graphs suggest. Measure 1m from the cone, not the listening position.


This IMO is a clear case of a listener who enjoys something other than a flat FR, and you should follow your ears. Dynamics are a bit hard to get from a single 6.5 midwoofer. My Current DIY mains use 2 6.5 Seas midwoofers in a 2.5 way sealed (the original ported design was too 'dry' for my tastes) with each over a single 12" sealed sub crossed at 100hz. The F3 of my mains are about 75hz so the xover point worked out well for me. Some will say you'll need to high pass the mains but i disagree. If you plug the port, the sealed alignment will move the F3 up higher creating a natural 12db/oct rolloff. The 6.5 midbass will also be relieved of the lower freq, improving the mid range clarity. In essence, your mains will perform more like 801s. You'll have to keep the subs in close proximity to the mains though to alleviate localizations at the higher XO, but like everything in audio...you have to live with the trade offs.

Yes. This is more of what I was thinking. Thank you.


Again, I have no time as I need to get to work, but I'll give you this:


Graph of B&W 805S's with and without port plugs measured at listening position:

Graph of B&W 805S's near field with port plugs (comparision of different x-over points):

These graphs seem to reinforce the idea that my little B&W's just aren't getting it done in that 80Hz - 160Hz region. This is what has me thinking I'd really benefit from a dual sub setup, one located at each speaker with a high x-over point like 160Hz.


So if this is the case, what subs? I'd love to try the ULS-15's, but that gets a little pricey. I'm willing to go that much, but they REALLY have to be worth it.


My SVS PB13U is really an incredible sub. So whatever I replace it with better be very special (and a little smaller hopefully).

 

[larry7995]

How about keeping the ultra and moving to the 804S or at least see if the dealer will let you demo a pair

 

[jkhome]



Quote:
Originally Posted by TJHUB /forum/post/15412000


Yes. This is more of what I was thinking. Thank you.

Your thinking is similar to what I am preparing to try in my HT system. I know this isn't the diy section, but the idea is the same.


Right now I have a 12" vented sub directly behind the seating area (on a sidewall). It's the best spot I have found in my medium size living room, performance wise compromised by that WAF issue. But I would like to have a more balanced bass output in the room, with more slam from the front stage.


The existing sub is an old HSU sonotube tabletop model, modded with a Rythmik non-servo driver, EQed with a DCX2496, and driven by a Mackie amp. (I originally bought two of each driver and amp, to build a second sonotube to add to the HSU.


But now I've picked up a Rythmik DS1500 kit, to mod the HSU into a 15" servo sealed unit, with it's own dedicated amp. So I plan on building two 1.8-2 cubic foot sealed enclosures for each of the two 12" Rythmik drivers, and (start by) trying them between the mains (Paradigm Studio 60s) and the display. These non-servo Rythmiks have a natural roll off at 100 hz.


Crossover wise, I'll set my receiver's bass management to "rears small, front L/C/R large, sub on". Then use an Outlaw ICBM downstream to bass manage the L/C/R. With my receiver, that will send part of the LFE signal to the rear sub, part to the ICBM, which can then be adjusted as needed. The back sub will cover the rear's bass management, the front subs for the L/C/R's.


That's the plan anyway

but Mayhem's idea sounds interesting also.

 

[mayhem13]

My suggestion includes keeping the SVS for LFE....You're not going to want to run up to 160hz in mono. Above 80hz, a lot of material such as male vocals wil be locatable and would smear the soundstage and stereo seperation.The Sub outs on your Arcam are parallel mono so you can't get a low passed stereo signal from those. The idea here is to include stereo Mid-bass modules and running rom 60-160hz that's pretty much what they'll be.


I suggest taking a look at these from rythik audio
http://rythmikaudio.com/F12.html


The Direct Servo technology will go along way towards a smooth mid-bass with dynamic transients. Especially with drum material where attack is everything on kickdrum and the bottom end of the snare.


P.S. There's a set of 803s on Audiogon for $3k in cherry.


The other option that someone pointed out is trading up your 805s

to a pair of 804s or better 803s. This may be financially in line with dual subs and should produce even better results given the xover work by B&W. I stopped in Stereo Exchange in NYC while Xmas shopping the other day and had a listen to a set of 802s and they were simply stunning in the low end run full range without a sub.

 

[mojomike]

A pair of HSU MBM12's would seem like a great solution for you.

 

[sivadselim]



Quote:
Originally Posted by TJHUB /forum/post/15410848


I want to agree with you, and you are most likely correct, but I'm at a loss as to what to do about my room. It's my living room and with some small exception, I can treat it with some panels, but I'm at a loss of just how to proceed.

As craig pointed out, your graphs do not look at all bad. No speakers are going to measure flat, in-room, unless you have treated the room so much that it no longer sounds like a room. But it's your living room, not an anechoic chamber. And you probably want to leave it that. Every speaker is going to sound different from room to room and every room is going to sound different from speaker to speaker, hence the dogmatic "listen to the speakers in your listening environment when auditioning".

Quote:
Originally Posted by TJHUB /forum/post/15410848


Graph of B&W 805S's near field with port plugs...............


These graphs seem to reinforce the idea that my little B&W's just aren't getting it done in that 80Hz - 160Hz region.

That's sort of what I would expect with the plugs in. Do you have near-field graphs without the plugs?


The graph above that, from the listening position, shows that the speakers do not really drop off at 160Hz, as the room is, as it should be expected to, reinforcing the low end. You have peaks and troughs, which is expected. The graph below 160Hz doesn't really have any different character than it does above 160Hz. Peaks and troughs, peaks and troughs. No big deal. That's how your speakers "sound" in your room.

 

[penngray]



Quote:
I can tell you that my setup has never sounded as good as it does right now.

really this is all that matters...we can measure all we want and modify our setups to please any chart but in the end all that matters is what sounds good to you.

 

[rabident]



Quote:
Originally Posted by TJHUB /forum/post/15409124


I love my B&W's and I really don't want to change them.

That room would look nice with a pair of 802's on front. I would move the 805's to the rear and put a pair of 802D's in there. No more bass issues other than the very low end which your current sub should be able to handle.

 

[SlowcarIX]



Quote:
Originally Posted by rabident /forum/post/15418064


That room would look nice with a pair of 802's on front. I would move the 805's to the rear and put a pair of 802D's in there. No more bass issues other than the very low end which your current sub should be able to handle.

you got any idea how much a pair of 802D goes for...?

 

[TJHUB]



Quote:
Originally Posted by sivadselim /forum/post/15414884


As craig pointed out, your graphs do not look at all bad. No speakers are going to measure flat, in-room, unless you have treated the room so much that it no longer sounds like a room. But it's your living room, not an anechoic chamber. And you probably want to leave it that. Every speaker is going to sound different from room to room and every room is going to sound different from speaker to speaker, hence the dogmatic "listen to the speakers in your listening environment when auditioning".



That's sort of what I would expect with the plugs in. Do you have near-field graphs without the plugs?


The graph above that, from the listening position, shows that the speakers do not really drop off at 160Hz, as the room is, as it should be expected to, reinforcing the low end. You have peaks and troughs, which is expected. The graph below 160Hz doesn't really have any different character than it does above 160Hz. Peaks and troughs, peaks and troughs. No big deal. That's how your speakers "sound" in your room.

I would like to be clear when I say that I'm not judging my setup by how it measures. I use my ears first and use the measuring for a visual aid as to what has happened with any changes I made. I did use the measurements to find the flattest response for my speakers, but that was really only a test.


What I was really looking for with the measurements was:


What happens when you move your speakers closer to the front wall; farther away?


What happens when you use more or less toe-in?


How does the left speaker measure by itself compared to the right speaker by itself?


What affect does my 2'x2'x2" acoustic panel have when located behind the speakers?


Of course I also use it to EQ my sub...


I'm really very happy with the overall sound of my setup. I absolutely love the midrange and treble of my B&W 805S's. I can play just about anything and find it pleasant. These B&W's make this the first time I've ever been able to make this statement.


The SVS PB13U is really VERY good as well. Even crossed as high as it is right now, it seems to dance across every low note effortlessly and never gets chesty sounding playing that midbass.


The problem is exactly that lack of attack when I try to cross the sub at 80Hz. It's just not there until I use the sub cross at 160Hz.


Solutions...


I'm not certain I want to fork out the cash to upgrade both my mains and center from the 805S and HTM4S to the 804S and HTM3S. I think that would be in the neighborhood of about $2,500.00 plus. I'd love to, but I just can't. I'm going to the city where my long standing B&W dealer resides. I'll give the owner a call tomorrow and visit him Friday. Who knows, maybe he can cut me some kind of deal...


I'm not certain I need the massive output of my SVS PB13U. I was thinking I could sell it and move to something like dual ULS-15's or maybe a pair of Rythmiks. This would only cost me about a $1,000.00 or so. If I could get the performance I need with dual subs, I think I can get what I'm looking for.


I didn't consider a pair of MBM-12's because I'm not all too thrilled with how they get hooked up. Maybe that's stupid on my part, but I'm looking for 2-channel bliss here over everything else.


I can consider replacing my speakers with something cheaper, but I'd really love to solve this with some sort of sub setup...


BTW: I really appreciate the comments and advice.

 

[Bone215]

TJHUB

This information may or may not be relevant.

I have never had the lack of punch in my system/room. Previous to my present set up I used the following combinations.

Set up 1

one JBL S120PII subwoofer below a JBL S38 on each side, wired direct to the sub and then out from the sub into the S38 using the subs preset 150Hz output. I thought at first that frequency would be too high, but, upon listening, it worked. It provided a relatively full range option, I ran them large, and kept my ACI Titan sub in the system playing the real low stuff. The JBL's were good down to 22 Hz in my room.

Set up 2

I later switched out the S38's when good fortune sent me JBL 4412A studio monitors. I used them with the subs below same as before with the same excellent results. Even more effortless than before.

The reason I bring this info to you is two fold:

1. the JBL subs are no longer available, but they have been replaced by a newer version, this one is sealed, not ported like the ones I had

2. they are available through various sources very cheap, so you could - if you wanted to - experiment with stereo subs underneath you L and R speakers, turning them into full range fronts capable of playing down in to the 22 to 25 Hz range. I beleive the subs still have the fixed 150 Hz hi level line out as did the previous model.

You could keep the ultra in the room for the 15 to 25 Hz stuff, using the built in crossover on the sub.

Having three subs in the room does provide, based on my experience, a lot of 'balance' in the bass. All of your 150 hz and below work is also being performed by powered units, freeing you main source of power to providing only 150Hz and up.

Of course, if your somewhat flush with cash, you could expand on this idea with even more expensive subs, like svs's sealed 12", perhaps sealed valors, or others, the concept remains the same.

Nice looking set up by the way, very clean.

Good luck in your 'hunt'. As you are probably very much aware, this 'hunt' may not have a conclusion, but at this stage, just more grey at different shades.